infinity vs multitude

infinity

noun
  • endlessness, unlimitedness, absence of a beginning, end or limits to size. 

  • A number that has an infinite numerical value that cannot be counted. 

  • The symbol ∞. 

  • A number which is very large compared to some characteristic number. For example, in optics, an object which is much further away than the focal length of a lens is said to be "at infinity", as the distance of the image from the lens varies very little as the distance increases further. 

  • An idealised point which is said to be approached by sequences of values whose magnitudes increase without bound. 

multitude

noun
  • A great amount or number, often of people; abundance, myriad, profusion. 

  • The mass of ordinary people; the masses, the populace. 

How often have the words infinity and multitude occurred in a corpus of books? (source: Google Ngram Viewer )